This invention relates to squash rackets, and, more particularly, to a squash racket which is lighter than prior squash rackets and which has a balance point or center of gravity which is closer to the head end of the racket than to the handle end.
Squash rackets conventionally have a length of about 27 inches and a weight of about 187 to 218 grams. Squash rackets are also usually "head light," i.e., the balance point or center of gravity of the racket is closer to the handle end of the racket than the head end. It is common to add lead or other weight to the handle of a squash racket in order to increase the weight of the racket, and the lead increases the "head light" characteristic of the racket.
Representative competitive squash rackets have been measured, and the physical properties of the rackets fall within the following ranges:
______________________________________ Weight Length Balance Iend (Grams) (Inches) (Inches) (oz. in..sup.2) ______________________________________ 187-218 26.9-27.08 12.04-13.73 1625-1909 ______________________________________
"Balance" is the distance of the balance point or center of gravity from the handle end of the racket. "Iend" is the moment of inertia about an axis at the end of the handle which extends perpendicularly to the handle and is a measure of the ability of the racket to resist rotation about the axis.
Frolow Reissue U.S. Pat. No. 31,419 describes a tennis racket which is lighter than conventional tennis rackets and in which weight is removed from the handle end and added to the head end to make the racket "head heavy," i.e., the balance point or center of gravity is closer to the head end of the racket than the handle end. Frolow also describes making the racket stiffer so that the frequency of vibration of the racket described in column 13 of FIG. 40 of the patent is greater than 140 cycles per second. The Frolow patent does not describe a squash racket, which is distinctly different than a tennis racket in shape, weight, and other physical characteristics.